Action On Mass Absenteeism

Dear Guidance Seeker
When you say Mass Leave first and foremost Question which springs up is --" Who sanctioned / granted Leave at a time to many for what all reasons ? Your Establishment must have approved Policy on Availment of Leave of Absence from Duty only when Leave applied for is sanctioned by appropriate sanctioning Authority in view of Exigencies of Work.
Your Post indicates Minimum Workplace Discipline was not followed
Kritarth Team is willing and ready to help
Kritarth Team
Bengaluru Service Unit
16.9.16

There must be come crucial cause for mass absenteeism.
you have to find out the issue. It should be attended by negotiations with the workman/employee leaders and to be solved.
Taking actions against them will aggravate the issue.